Thursday, April 2, 1998 Published at 19:49 GMT 20:49 UKWorld: AnalysisPilgrims begin the Hajj in MeccaPigrims surround the Kaba'a in Mecca

This year's Hajj began on March 28, with an estimated two million Muslims gathering in Mecca, the birthplace of Islam in Saudi Arabia. Pilgrims come from all over the world to take part in a series of religious rituals, which this year culminate on the April 6. Kate Clark from the BBC's Arabic Service reports on what is the biggest yearly religious gathering in the world:

The Koran calls on all Muslims to make the pilgrimage, if they have the means. Muslims believe that the reward for performing the Hajj is nothing less than Paradise, but it's important to carry out all the rituals correctly.

They're complicated and last ten days. The most famous is when the pilgrims walk round the Kaba'a - the black stone building in Mecca. Plgrims also have to travel to nearby Mina and camp overnight in tents and there are special prayers which have to be said.

All these rituals are based on actions which the Prophet Abraham made when God tested his faith by asking him to sacrifice his son Isma'il.

The Hajj is a huge occasion, with two million people of all nationalities and backgrounds concentrated into just a couple of square miles in Mecca. The very number of people means that, logistically, performing the Hajj can be difficult.

It can also cause dangers - last year, 300 people died as a fire swept through 70,000 tents in Mina.

In the past, pilgrims could take months or even years just travelling to Mecca. It was a dangerous undertaking, with many dying in the attempt to reach the sacred shrines.

There were tales of bravery and luck - escaping robbers or slave-traders, crossing the Sahara on foot from West Africa or sailing in overcrowded boats from India. Nowadays, pilgrims fly in to one of the world's most modern airports, in a matter of hours.

The Hajj isn't just a time for spiritual matters. Most people take presents back to family and today, there's a significant trade in electrical goods. The Hajj has always been an important source of income for the people of Mecca - honest commerce isn't frowned on in Islam.

Inevitably, politics also figures. Already, this year, there have been complaints from Iran that Saudi security forces have been harassing their pilgrims. The Saudis have denied this, but there's a history of tension dating back to the Islamic revolution in Iran in 1979 - both Saudi Arabia and Iran feel that they speak for the Islamic world.

In 1987, the Saudi police opened fire on such an Iranian demonstration, killing over 400 pilgrims. But relations between the two regional heavy weights have been improving and no major incidents are expected this year to marr the pilgrimage.